HOW DO WE MAKE HEARING AID SOUND?
The best way to make sure that a hearing aid sounds good is to test it… and test it … and test it … and test it … thousands of times. But whose job is it to create and test the sound that comes out of your hearing aids – and how is it done?
That job belongs to the Widex Research and Development team – a group of engineers who work tirelessly to ensure that the “Widex Sound” is the most natural hearing aid sound around.
The listening test
Jens Peter Holmegaard is one of the faces behind the Widex sound. He’s a hearing aid research and development engineer who has been designing Widex hearing aids for 7 years.
We sat down with Jens and asked how he and his colleagues make sure that sound from our hearing aids is as true to real-life as it can possibly be.
And the answer is simple: he listens.
He listens to everything – from speech, to music, to the sound of a microwave. It’s Jens’ job to make sure that the sounds of your everyday life are perfectly replicated by your hearing aids.
“Our library of sounds includes everything from water running in the sink, to pork chops frying, to birds singing,” says Jens. “They’re all sounds that have characteristics that are important to the hearing aid user.”
But listening to those sounds once isn’t enough. With every small tweak or change comes a new round of testing – which means listening to those sounds hundreds or even thousands of times.
“I become very familiar with those sounds,” says Jens. “They’re often not sounds I want to hear when I get home.”
And it’s not just everyday sounds – it’s music too. A favorite test song at Widex is Suzanne Vega’s “Tom’s Diner” because of its range of tones and pitches. It also has a steady bass line and a repetitive chorus - all good for testing purposes.
Creating the Widex sound
To find out more about how Widex hearing aids get their true-to-life sound, it’s important to take a step back to where the whole process begins. Developing a new hearing aid can often take five or more years and it all starts with the experiences and wishes of existing hearing aid users which are gathered and transformed into ideas for new products at the engineers´ drawing board.
For example, Widex got the idea to develop its audibility extender after realizing that some hearing aid users were having difficulty hearing upper frequency sounds. The extender moves these sounds to a lower frequency region where it is easier to hear them.
After the brainstorming phase, ideas are scheduled for development. That’s where the sound library comes in. As features like the audibility extender are created, rounds of testing begin. Sounds like birdsong, bells, and timers are used to test upper frequency sounds that the audibility extender helps hearing aid users to hear.
“It gives us a frame of reference for the hearing aid feature we are developing,” says Jens. “We listen to how this feature helps the sound in real-life situations and tweak it to make it sound as natural as possible.”
The final test
After a feature is developed, the technology is added to the physical hearing aid. But that’s not where the story ends. Hearing aids are then tested again by specially-trained sound expert who make sure that the technology is working correctly.
Hearing aids are then produced and shipped to your hearing professional, who will program them to fit your particular hearing loss.
Which hearing aid features have Widex developed over the past years? Here are just a few of the ones found in our devices:
Audibility Extender - The Audibility Extender helps people with high frequency hearing loss to hear upper frequency sounds by moving these sounds to a lower frequency region where it is easier to hear them. The upper frequency sounds are important for hearing the “softer” sounds like /s/ and /t/ in women´s and children´s voices and high-pitched sounds like the “ping” of the microwave.
Telecoil - A telecoil is a small coil inside your hearing aids. The coil works as a small receiver which picks up signals from a loop system that acts as an electromagnetic field. Hearing aids with an activated telecoil can convert this electromagnetic field into a sound signal. Only the signal from the loop system’s microphone is amplified, and background noise is shut out.
Speech Enhancer - The Speech Enhancer is different from simple noise reduction systems in that it doesn´t just dampen noise - it also amplifies speech. When we listen to a sound, we are rarely in doubt as to whether it is speech or noise. The Speech Enhancer in modern hearing aids is able to distinguish the two in much the same way as our brains do – by using the fact that speech consists of a number of varying sound components that follow each other at brief intervals.